Synergistic alpha-naphthyl nu-methylcarbamate insecticide admixed with meta-acetylphenyl or meta-propionylphenyl nu-methyl carbamate



May 21, 1968 J. MOCOTTE 3,384,539

SYNERGISTIC ALPHA-NAPHTHYL N-METHYLCARBAMATE INSECTICIDE ADMIXED WITH META- ACETYLPHENYL OR META-PROPIONYLPHENYL N-METHYL CARBAMATE Filed July 1, 1965 4 Sheets-Sheet l ay 21, 1968 J. MOCOTTE 3,384,539

SYNERGISTIC ALPHA-NAPHTHYL N-METHYLCARBAMATE INSECTICIDE ADMIXED WITH META-ACETYLPHENYL OR META-PROPIONYLPHENYL N-METHYL GARBAMATE Filed July 1, 1965 4 Sheets-Sheet 2 1968 J. MOCOTTE 3,384, SYNERGISTIC ALPHA-NAPHTHYL N-METHYLCARBAMATE INSECTICIDE ADMIXED WITH META'ACETYLPHENYL OR META'PROPIONYLPHENYL N-METHYL CARBAMATE Filed July 1, 1965 4 Sheets-Sheet 3 y 21, J. MOCOTTE 3,384,539

SYNERGISTIC ALPHA-NAPHTHYL N-METHYLCARBAMATE INSEGTICIDE ADMIXED WITH META-ACETYLPHENYL OR META-PROPIONYLPHENYL N-METHYL CARBAMATE Filed July 1, 1965 I 4 Sheets-Sheet 4 United States Patent SYNERGISTIC ALPHA-NAPHTHYL N-METHYL- CARBAMATE INE CTTTDE ADMIXED WITH META ACETYLPHENYL 0R META PROPHE- NYLPHENYL N-METHYL CARBAMATE Jacques ll Iocotte, Champagnc-au-Mont-dflr, Rhone, France, assignor to Progil, iaris, France Filed .luly l, 1965, Ser. No. 468,873 Claims priority, application France, July 3, 1964, 980,673 8 Claims. (Cl. 167-30) ABSTRACT 0F THE DISCLOSURE New synergistic insecticidal compositions which are a mixture of alpha-naphthyl N-methylcarbamate and at least one phenyl carbamate having an acyl substituent on the phenyl ring in the meta-position.

This invention relates to new compositions exhibiting synergistic insecticidal properties, which compositions are mixtures of organic carbamates.

In the following specification all parts and percentages are given by weight unless otherwise indicated.

It is Well known that several aryl esters of carbamic acid, which may be mono-substituted or di-substituted at the nitrogen atom, have good insecticidal properties. One of the most active compounds of this group is alphanaphthyl N-methyl carbamate.

It has also been shown in the prior copending US. application Ser. No. 362,220, filed Apr. 24, 1964 that some phenyl esters of carbamic acid in which the phenyl ring contains an acyl group in the meta position are outstanding insecticides which are more active than the I car-bamic derivatives already known for such purposes, more particularly alpha-naphthyl N-methylcarbamate (see French Patent No. 1,381,253 of Apr. 25, 1963).

It has now been found that, when alpha-naphthyl N- rnethylcarbarnate is associated with at least one carbamate of meta-acylphenyl, the insecticidal activity of the resultant mixture is much greater than that of each of the known constituents. It is particularly higher than that of the carbamate of meta-acylphenyl, which itself is far superior to the activity of alpha-naphthyl N-methylcarbamate.

The new insecticide according to the invention comprises a mixture of alpha-naphthyl N-methylcarbamate and at least one carbamate of meta-acylphenyl of the following formula C ORa wherein R and R which may be the same or different, may be hydrogen atoms or lower alkyl groups having from 1 to 4 carbon atoms, R is a lower alkyl group having from 1 to 4 carbon atoms, X is a hydrogen atom or an electronegative group such as halogen, particularly chlorine, bromine or fluorine, or N0 and n is an integer of from 1 to 3.

The meta-acylphenyl component of the novel mixtures of the present invention may, for example, be one of the following compounds: m-acetylphenyl carbamate, m-propionylphenyl carbamate, m-butyrylphenyl barbarnate, m-(alpha-methylacetyl) phenyl carbamate, macetyl p-chlorophenyl carbamate, m-acetylphenyl-N- methyl carbamatc, m-acetylphenyl N-ethylcarbamate, macetylphenyl N-N-dimethylcarbamate; m acetylphenyl N-N-dibutylcarbamate, m-acetylphenyl N-methyl N- ethylcarbamate, m-acetylphenyl N-rnethyl N-isopropylcarbarnate, etc.

The proportions of each of the carbamates according to this invention may vary within wide limits, for example 99 to 1 part by weight of alpha-naphthyl N-methyl carbamate to l to 99 parts of m-acylphenyl carbamate. However, to obtain an appreciable synergistic effect, it is particularly advantageous to use from 90 to 25 parts of alphanaphthyl N-methylcarbamate to 10 to parts of m-acylphenyl carbamate. If for example, m-acetylphenyl N-methylcarbamate is used, a very distinct synergistic activity is found with 10 parts of this carbamate (A) and parts of alpha-naphthyl N-methylcarbamate (B). If the proportions of product A are increased, for example, to 25 .parts to 75 parts of B, the efiicacy of the product A alone, which is already more active than product B alone, is exceeded. When the respective proportions of A and B range from 50 to 75 parts, the synergistic activity is spectacular, the efiiicacy of the mixture being 2 or 3 times greater than that of product A used alone in the same proportion.

The insecticidal compositions hereof may be applied in different forms, e.g., as mixtures with water-wettable powders or in suspensions, solutions or emulsions, with inert liquids. The mixtures may be applied by any suitable technique, e.g., by vaporization, coating or impregnation of the materials to be protected. When the compositions hereof are employed in solution form they may be dissolved in one or more inert solvents, such, for example, as aromatic hydrocarbons, e.g., benzene, toluene, xylene, decaline; chlorinated hydrocarbons, such as carbon tetrachloride, perchloroethylene; esters or ethers, e.g., alkyl propionates or acetates, dioxane, tetrahydrofuran; ketones, such as acetone, methyl-ethyl ketone, cyclohexanone, etc. Such solutions contain from 0.5 to 20% by weight of the active mixture, preferably from about 1 to 10% by weight of same.

For some applications it is preferable to incorporate the insecticidal compositions hereof in an emulsion, a conventional surface active agent being employed, to emulsify the mixture in an aqueous external phase.

Alternatively, the mixture may be provided as a waterwettable powder admixed with a suitable support, such as talc, kaolin, silica gel, etc., and thus impregnated with from 0.05 to 5% of an appropriate surface active agent. The resulting pulverulent mixture, which generally contains from about 10 to by weight of the active mixture, may be employed in dry form, without the addition of a surfactant, and without dilution with water.

In general, the active mixture may be supplied to users in the form of compositions containing from 0.5 to 99.5% of the carbamate mixture, the balance of such compositions comprising one or more of the hereinabove mentioned inerts, e.g., solvents, liquid dispersants, Water, in organic pulverulent fillers, surfactants, or the like.

In the following examples which are intended as illustrative and not in a limiting sense, the insecticidal activities of alpha-naphthyl N-methylcarbamate, m-acetylphenyl N-methylcarbamate, and of the mixture of such compounds have been compared. The comparative activities are graphically illustrated in the accompanying drawings, FIGURES 1 and 2 of which illustrate the comparative activities determined in Example 1, and FIG- URES 3 and 4 of which illustrate the comparative activities determined in Example II, which concerns. the use of metapropionyl-phenyl N-rnethyl-carbamate.

EXAMPLE 1 Solutions of alpha-naphthyl N-methylcarbamate (B), m-acetylphenyl N-methylcarbamate (A) and mixtures of these carbamates, in acetone, were sprayed very finely inside Petri dishes. A series of five sample dishes, all containing the same amount of the product under examination, Le, 25 mg. per square meter of area, were then prepared for each type of product or mixture. One Petri dish free from carbamate was put aside as a control. The same number of insects under test of the type Calandra granaria, 100 males and females, were introduced into each box, and the number of dead insects was counted at regular intervals. Each test was repeated five times for the above concentration, the final result being the mean of the results obtained with the five Petri dishes used.

The mixtures of carbamates A and B studied had the following respective compositions (per 100 parts by weight) A, parts: E, 90 parts; A, parts: B, 75 parts; A, 50 parts: B, 50 parts; A, 75 parts: B, 25 parts.

The results obtained are shown, only partially for greater clarity, in the curves in FIGURES 1 and 2 accompanying this description.

The ordinate in FIGURE 1 denotes the percentage of actual mortality of the insects while the abscissa denotes the number of hours the insects were in contact with the insecticide under examination. The curves at and b correspond to proportions of 25 mg. per square meter, respectively, of m-acetylphenyl N-methylcarhamate and alphanaphthyl N-methylcarbamate. Curve c corresponds to the mixture by weight: 25 parts of A plus 75 parts of B, white curves d1 and d2 combined into a single curve d show the mixtures of: 75 parts of A+25 parts of B and 50 parts of A+50 parts of B. Of course, the respective proportions used are the same as those which gave curves a and b, i.e., 25 mg. of active substance per square meter of area.

Curves d1 and d2 have been combined on the graph because the activity of the two types of insecticidal mixtures was substantially identical. Curve t, which corresponds to the control test, is a straight line which coincides practically with the abscissa.

From these curves it will be seen that for a given dose of active substance the mixtures of alpha-naphthyl N- methyl-canbamate and rn-acetylphenyl N-rnethylcarbamate have a much greater efiicacy than that of the superior one of these car-barnates. For example, at the end of 48 hours the mortality rate is about 26% for alphanaphthyl N-methylcarbamate and 80% for m-acetylphenyl N-methylcarbamate, while it is 95% in the case of the mixtures: 75 parts of B and 25 parts of A, and the maximum mortality rate of 100% is already achieved after 3 hours with the other two types of mixtures denoted by curve d.

In order to show more clearly the synergistic effect of the mixture of the types of carbamates according to this invention, FIGURE 2 shows the activity of different mixtures by comparison with the two canbarnates alone, along the line x y at the time of hours in FIGURE 1. The ordinate again shows the actual mortality as a percentage while the abscissa denotes the respective percentages from 0 to 100 of m-acetylphenyl N-methylcarbamate (A) and alpha-naphthyl N-methylca-rbamate (-B). If we compare the straight line e, which denotes EXAMPLE 2 Tests were carried out under the same conditions as in Example 1 except that m-acetylphenyl N-methylcar- I bamate (A) was replaced by rn-propionylphenyl N-methylcarbamate (A).

The mixtures of the carbarnates A and B under study also had the same compositions by weight.

The results are shown in FIGURES 3 and 4 accompanying this description.

In FIGURE 3, in which the ordinate is again as in FIGURE 1, the curves :1 and b correspond to proportions of 25 mg. per square meter, respectively, of mpropionylphenyl N-methylcarbamate and alpha-naphthyl N-methylcarbamate. Curve 0' corresponds to the mixture by weight: 25 parts of A+75 parts of B. Curve d illustrates mixture: 75 parts of A and 25 parts of B, and curve e corresponds to the mixture: 50 parts of A'+50 parts of B. In every case the proportions used were 25 mg. of active substance per square meter of area.

It is apparent from these curves that the activity of the mixtures of alpha-naphthyl N-methylcarbarnate and m-propionyiphenyl N-rnethylcarbamate is much superior to that of the better one of these carbamates.

The synergitsic effect is very clearly shown by the curves in FIGURE 4 which were plotted under the same conditions as those applying to FIGURE 2 (Example 1). The synergy area S framed by the straight line 1 (theoretical activity line of mixtures A and B) and curve g1 and g2 (corresponding to actual activities of the mixtures of the two carbarnates) is clearly shown in FIGURE 4.

It will thus be seen that the present invention provides a novel composition exhibiting synergistic insecticidal properties. Since various changes may be made in the preferred embodiments of the compositions of the present invention described hereina-bove without departing from the scope of this invention, it is intended that the preceding description be construed as illustrative and not in a limiting sense.

I claim:

1. A composition exhibiting synergistic insecticidal properties, comprising a mixture of to 25 parts by weight of alpha-naphthyl N-methyl-carbamate and 10 to 75 parts by weight of at least one carbamate selected from the group consisting of meta-acetylphenyl N-methyl carbamate and meta-propionylphenyl N-methyl carbamate.

2. The composition defined in claim 1, wherein said meta-acyl-phenyl carbamate is meta-acetylphenyl Nmethylcarbamate.

3. The composition defined in claim 1, wherein said meta-acyl-phenyl carbamate is meta-propionyl-phenyl N- methylcarbamate.

4. The composition defined in claim 1, wherein said mixture is dispersed in an inert solvent, the resulting dispersion containing from 0.5 to 20% by weight of said mixture.

5. The composition defined in claim 1, wherein said mixture is emulsified in an aqueous outer phase.

6. The composition defined in claim 1, wherein said mixture is admixed with a water-Wettable powder, the resulting pulverulent mixture containing from 10 to by weight of the mixture exhibiting insecticidal properties.

'i. A composition exhibiting synergistic insecticidal roperties comprising a mixture of alpha-naphthyl N- methylcarba-mate and meta-acetylphenyl N-methylcarbamate in the proportions of from 90 to 25 parts by weight of the alpha-naphthyl N-methyl carbamate, per

5 6 10 to 75 parts by weight of the meta-acetylphenyl N- References Cited rnethylcarbamate, said mixture being dissolved in acetone UNITED STATES PATENTS 1n an amount of from 1 to 10% of the solution.

8. A composition exhibiting synergistic insecticidal 3,009,855 11/1961 Lambrech 167-32 properties, comprising a mixture of alpha-naphthyl N- 5 FOREIGN PATENTS methylcarbamate and meta-prop1onyl-pheny1 N-rnethyl- 1,381,253 11/1964 France.

carbamate in the proportions of from 90 to 25 parts by weight of the alphanaphthyl N-methyl carbamate, per 10 I to 75 parts by Weight of the meta-propionyl-phenyl N- LEWIS GOTTS Prlmmy Examine" methylcarbamate, said mixture being dissolved in acetone 10 ROSE, Assistant Ex n in an amount of from 1 to 10% of the solution. 

